Propellent smokeless-powder charge



UNITED STATES PATENT omca.

CLARENCE I. n. EENNING, 0E WILMINGTON, DELAWARE, 'AssIcNoE 'ro E. 1. m,P m: NEMZOUBB & COMPANY, or WILMINGTON, DELAWARE, a oonromuaron OFDEL-AWARE.

PROPELLEN T SMOKELESS-POWDER CHARGE.

1,393,623. Specification of Letters Patent. Io Drawing.

To all whom it may concm:

Be it known that I, CLARENCE I. B. HEN- NING, a citizen of the UnitedStates, and a resident of Wilmington, in the county of New Castle andState of Delaware, have invented a certain new and useful PropellentSmokeless-Powder Charge, of which the following is a specification. IThis invention relates to a charge of progressive burning smokelesspowder of the surface treated type, and comprises a charge in whichnitrocellulose powder of the above mentioned character is associatedwith a supplementary priming charge consisting essentially of an easilyignitible propellant, such as black powder.

While all smokeless powders are progressive burning, the termprogressive burning powders has in recent years 'been applied to powdersof the surface treated type which are extensively used in militaryrifles. In

powder of this type the burning of the powder grain is regulated bytreating the surface of the powder grain with a deterrent material or adeterrent explosive, or a mixture of these, causing the outer layer ofthe powder to burn more slowly, which results in reduced pressure at thebreech of the gun and does not'unduly increase the pressure along thebore of the rifle- As might be expected, surface treated powders aremore difficult to ignite than non-surface treated powders but thisdifliculty in ignition has been largely overcome by the use of decidedlystronger primers. Thus, by the use of decidedly stronger primers for theignition of surface treated powders, ballistic results have beenobtained very much in advance over ballistic results obtainable fromnon-surface treated powders. In view of this fact that surfacetreatedpowders have been used uite successfully in this manner, it hadnot een realized that greater possibilties existed in connection withthe use of powder of this type.

I have discovered an improved method of ignition for progressive burningpowders of the surface treated type which makes it possible to obtainballistic results far in advance of those which it is possible to obtainwithout using my invention. I have found that it is possible to obtainimproved ballistic results by using for a charge of progressive powderof about 50 grains a supplementary ture of materials, or to PatentedOct. -11,- 1921.

Application filed. January 16, 1920. Serial No. 351,894.

black powder priming charge of more than one gra n and in general fromabout two to five grains, 1I 1 add1t1on to the usual primer for thelgnltion of progressive burning powders of the surface treated type.More especially I have found that, by using a supplementary black powderpriming charge in a'ddltlon to the usual primer, it is possible toreadily ignlte progressive burning powders of the surface treated typewhich up to the present tlme have been impossible of ignition or yerydifficultly ignited by the usual prlmers alone, due either to the use ofa partlcular surface treating material or a mixthe use of an excessiveamount of surface treating material thereby producing powder grainswhose surfaces are difficult or impossible to ignite by means of theusual primers alone. Therefore, by 'belng able to produce properignition of progressive burning powders of the surface treated type,whose surfaces have been treated with a greater amount of deterrentmaterial or deterrent explosive, or mixture of these, than heretoforeused, I have obtained an improved propellent powder giving remarkableballistic results, as evidenced by a very decided reduction in pressure.It is, therefore, possible to obtain a very decided increase in thevelocity of the pro ect1le and at the same time with a pressure notexceeding the pressure given by the usual propellent powders and in. agreat many cases with a still lower pressure. Further advantages of myinvention are that the use of a propellent powder at such a low pressureis accompanied by a decided reduction in the erosion because of thelower temperature at which the powder is consumed. In addition, there isdecided reduction in My invention may be illustrated by the followingexample The powder used may be made according to the usual processes formaking progress1ve burning powder of the so-called surface-treated type.For example, suflicient nitrocellulose to give 100 parts by weight ofnitrocellulose, which may be a mixture of nitrocellulose soluble inether; alcohol with nitrocellulose relatively insoluble inether-alcohol, or may besoluble nitrocellulose alone, is dehydrated withethyl alcohol of approximately 95% strength by volume ents Nos.1,310,848, 1,312,463

by means of a dehydrating press in order displace the water. The excessalcohol is removed from the nitrocellulose, leavin about 33% parts, byweight, of the alcoho in the dehydrated nitrocellulose. To this is addedapproximately 66?; parts by weight of ethyl ether in a suitable mixingmachine, preferably provided with brine refrigeration. To thenitrocellulose and solvent in the mixer there may be added one-half ormore parts of diphenylamin or other Stabilizer, together with graphite,powdered metals, nitrocompounds, etc., in varying amounts. Thecomposition is thoroughly mixed and colloided, which operation in themixer requires about one-half hour or more,

depending on the efliciency of the mixer. After thoroughly mixing, thecolloided comosition is formed into preliminary blocks y means of apress. These blocks are then pressed in the so-called finishin press andthe composition pressed throug dies mto strings, which strings aregranulated by means of. a cutting machine. The granulated powder is thenplaced for one or more days in solvent recovery apparatus to recover thealcohol and ether, and then dried in water or air to reduce thesolventremaining in the powder to a low amount. The powder is then surfacetreated with a deterrent material such as dimethyldiphenylurea or adeterrent explosive such as dinitrotoluene or a mixture of these two orother ingredients. The details of this surface treating process, whichforms no part of the present invention, are described in U. S. Patand1,313,459. refer to use y used for The black powder which I is of thecomposition genera black sporting powder and of approximately the folowing composition 74.0% potassium nitrate,

10.4% sulfur,

15.6% charcoal.

However, I do not limit 111 elf to any particular composition of blachpowder as it is obvious that I would use that composition which by testsgives the best results and likewise that granulation whichby tests isfound most suitable for the particular purpose desired. Thissupplementary priming charge is then mixed with thepro ive owder grains;or it may be place in the ase of the shell; in any case thesupplementary charge should be so associated with the progressiveburning1 powder as to be in direct contact therewit Nitrocellulosepowder grains prepared as described in the first part of the aboveexample, but before surface treatment, gave in the .30/06 Springfieldrifle with the regular U. S. Government primed shell and with the180-grain bullet an instrumental velocity at 78-feet of 2,481 feet persecond, with a mean pressure of 48,950 pounds per square the surface Ido not limit myself to the use of black powder or to the use of blackpowder containin saltpeter as many nitrate mixtures will give the sameimproved i gressive burning powders 0 treated type as the tion givenabove.

Instead of black powder or nitrate mixtures I may use nitrocellulosepowder grains, nitrocellulose-nitro l cerin' powder rains, orpowdergrains ot t e semi-smokeess type, t at is a mixture of blackingredients, sulfur, charcoal and sa t with nitrocellulose or groundnitroce powders. In fact I may nitible propellant such as small arms andordnance, tary priming charge to the order to obtain better ignition ofthe more difiicultly ignited progressive burning powdei's (11f thesurface-treated type.

1. A propellent charge comprising uprogressive bu'rmng nitrocellulosepowder of treated type associated with a the su black powder composiwderter, 9 use any easi y might be used l n as a supplemention of usualprimer in supplementary priming charge oonsistinfi es- I ent sentiallypowder. I

2. A propellent charge comprising a progressive burning nitrocellulosepowder of the surface treated type intimately mixed with a supplementarypriming char consisting eaentially of an easily ignitib e propellentpowder.

3. propellent charge comprising a progresslve' burning nitrocellulosepowder of the surface treated type associated with a supglementarypriming charge containing sul r, charcoal, and potassium nitrate.

4. A propellent charge comprising nitrocellulose powder grains carryinga deterrent material at their surface, associated with an easilyignitible propellent powder.

5. .A propellent charge comprising 50 parts of nitrocellulose powdergrains carrymg a deterrent material at their surface assoclated withfrom about 2 to 5 parts of an easily ignitible propellent powder.

6. A propellent charge comprising nitrocellulose powder grains carryinga deterrent material at their surface, associated with a of an easily,ignitible prope su glementary priming charge containing material attheir surface, associated with a supplementary priming charge containingsulfur, charcoal, nitrocellulose, and potassium nitrate.

8. A propellent charge comprising nitro cellulose powder grainsimpregnated with a deterrent material, associated with a relativelysmall amount of a propellent powder containing sulfur, charcoal, andpotassium nitrate.

9. An explosive composition comprising a mixture of about 50 parts ofprogressive burning smokeless powder of the surface treated type withfrom about 2 to 5 parts of a powder containing sulfur, charcoal, andpotassium nitrate.

10. An explosive composition comprising a mixture of about 50 parts ofrogressive burning smokeless powder of t e surface treated type withfrom about 2m 5 parts of a powder containing sulfur, charcoal, andpotassium nitrate in the proportions of about 2 parts sulfur, 3 partscharcoal, and15 parts potassium nitrate.

11. An ex losive composition comprising a mixture 0 about 50 parts ofprogressive burning smokeless powder of the surface treated type withfrom about 2 to 5 parts of a powder containing sulfur, charcoal,nitrocellulose, and potassium nitrate.

12. A propellent charge comprising nitrocellulose powder grains carryingat their surface a deterrent explosive, associated with a supplementarypriming charge consisting essentially of an easily ignitible propellentpowder.

13. A propellent charge comprising nitrocellulose powder grain'scarrying at their surface a deterrent explosive, associated with asupplementary priming charge consisting essentially of sulfur, charcoal,and potassium nitrate.

14. A propellent charge comprising nitrocellulose powder grains carryingat their urface a deterrent explosive, associated with a supplementarypriming charge consisting essentially of sulfur, charcoal,nitrocellulose, and potassium nitrate.

15. A propellent charge comprising nitrocellulose powder grains carryingat their surface a deterrent explosive, associated with a supplementarycharge consisting essentially of nitroce'llulose-nitroglycerin powdergrains.

In testimon whereof I aflix m si nature.

CL RE-NCE I. B. HE Nl lNG.

